I always use the Basic mode in KCleaner, using the Clean button. But whenever I run it, it seems to hang while it says "Windows installer duplicates." It may sit there, seemingly doing nothing, for maybe 1 or even 2 minutes. Once it gets to other things though, it seems to move along more quickly. (This is an intermittent problem.) What am I doing wrong?

What is the location of these Windows installer files on the hard drive? Can I delete them manually? Why isn't KCleaner deleting them? (Or, maybe it is cleaning them out but it keeps checking for them anyway?)